Lamp guiding and mounting means



1952 T. B. FARRINGTON 2,618,454

LAMP GUIDING AND MOUNTING MEANS Filed Aug. 21, 1946 4 Sheets-Sheet lINVENTOR THAYER B. EARRING-TON A T TORNE YJ Nov. 18, 1952 T. a.FARRINGTON LAMP GUIDING AND MOUNTING MEANS 4 Sheets-Sheet 2 Filed Aug.21, 1946 ,wvzslvron THAYER B. fhRR/ ero/v ATTORNEYS IN ME N 7' 0/? TH:YER 2S. PARKING-TON ATTORNEY-5 4 Sheets-Sheet 3 Q! a a 4,

T. B. FARRINGTQTJ LAMP GUIDING AND MOUNTING MEANS Nov. 18, 1952 FlledAug 21, 1946 Nov. 18, 1952 "r. B. FARRINGTON LAMP GUIDING AND MOUNTINGMEANS 4 Sheets-Sheet 4 Filed Aug. 21, 1946 pllllllll' //V VEN TOR THAYER:5. Sam/warm ATTGRNETJ Patented Nov. 18, 1952 LAMP GUIDING AND MOUNTINGMEANS Thayer B. Farrington, Cleveland Heights, Ohio, assignor to TheThompson Electric Company, Cleveland, Ohio, a corporation of OhioApplication August 21, 1946, Serial No. 692,023

6 Claims.

This invention relates to improvements in lamp guiding and mountingmeans.

An object of the present invention is to provide a lamp in an elevatedposition with a novel, generally vertical, hollow track leading upwardlyto a position adjacent the lamp, there being a novel carriage movable upand down on the track for the purpose of carrying the lamp upwardly toan elevated position when in use, or for carrying the lamp downwardlyfor repairs and maintenance when such is required.

Another object of the present invention is to provide such a hollowtrack as a means for housing the operating cable by which the lamp israised and lowered.

Another object of the invention is to provide novel means whereby thehollow track houses the electrical conductors which energize the lamp.

Still another novel feature of the invention is the utilization of thehollow track as a housing means for both the operating cable for raisingand lowering the lamp and for the electrical conductors for energizingthe same, together with means for maintaining a separation between thecable and conductors. This phase of the invention may combine the hollowtrack with a hollow arm for supporting the lamp, wherein the operatingcable and electrical conductors pass through the hollow arm, andpartition means in the arm separates the cable from the conductors.Thus, the cable and conductors may be separated all the way through thetrack and through the arm to the lamp itself.

Another object of the present invention is to provide a carriage forguiding the lamp upwardly and downwardly and novel means mounting thecarriage on the track.

Still another object of the present invention is to provide novelcarriage mounting means on the guiding track wherein a roller on thecarriage bears against the track to yieldingly support the carriage forlimited movement toward and away from the track supporting structure,while other rollers yieldingly engage the sides of the track to supportthe carriage for limited movement laterally, and flanges on these lastnamed rollers engage behind laterally projecting portions of the trackso as to positively hold the carriage on the track.

Other objects and advantages of my invention include the combination ofa hollow track of box beam section permitting light gauge metal to beutilized for the formation of a structurally strong track, which at thesame time, provides laterally projecting hollow portions fulfilling thedouble purpose of housing electrical conductors and providing guidingportions for the carriage.

Other objects and advantages of the present invention will be apparentfrom the accompany- 2 ing drawings and description, and the essentialfeatures thereof will be summarized in the appended claims.

In the drawings,

Fig. l is a side elevational view of one form of my device;

Fig. 2 is a front elevational view, enlarged, of the carriage portion ofFig. 1 taken in the position of the line 22 of Fig. 1;

Fig. 3 is a side elevational view, enlarged, of the carriage portion ofFig. 1;

Figs. 4 and 5 are transverse sectional views taken along similarlynumbered lines of Fig. 2;

Fig. 6 is a fragmental sectional view taken along the line 6-6 of Fig.5;

Fig. 7 is a sectional view taken along the line 1--1 of Fig. 3;

Fig. 8 is a sectional view taken along the line 8--8 of Fig. 3 andshowing a supporting insulator for the electrical conductors;

Fig. 9 is a side elevational view of a modified form, this view beingtaken in the same relative position as Fig. 3;

Fig. 10 is a front elevational view of the device of Fig. 9 taken fromthe left-hand side of Fig. 9;

Figs. 11 and 12 are transverse sectional views taken along similarlynumbered lines of Fig. 10;

Fig. 13 'is a sectional view taken along the line |3--l3 of Fig. 9;while Fig. 14 is a sectional view similar to Fig. 13, but taken at apoint where a supporting insulator for electrical conductors isinserted.

The present invention has for its purpose the provision of a generallyvertical track for guiding a lamp to an elevated operating position froma lowered position where the lamp is accessible for repairs andmaintenance. Such lamps have previously been guided by cables whichpermit a certain amount of lamp movement in high wind and which are alittle diificult to operate if the guiding cable becomes coated with icein the winter. Vertical tracks have been used for the guiding of suchlamps, but the present invention overcomes certain difiiculties of theseprior devices by providing a track which is cheap to construct, butnevertheless, strong and efiicient for the purpose intended, and whichprovides a continuous closed passageway from top to bottom for housing alamp operating cable or electrical conductors, or both. The inventionalso provides novel means for mounting the lamp supporting carriage onthe vertical track so that the same may be readily removed from thetrack, if necessary, and so that the carriage will traverse the trackunder all conditions of icy weather, corrosion, and like obstructions.

In the form shown in Figs. 1 to 8 inclusive, a lamp supporting fixture l5 similar to that shown in my Patent No. 2,303,626, granted December 1,1942, is indicated as supporting one or more lamps within the globe I6.Preferably, two such lamps on opposite sides of the fixture areprovided, as shown in said patent. Those skilled in this art willunderstand that the globe It might be red in the case of lamps mountedon high structures for airplane warnings. The lamps carried by thefixture it are supported from above by the fixture stem ii a which isanalogous to the stem 35 of my said patent. A canopy I? is supported bymeans of hollow arm it on the supporting structure l9 which may be ahigh building, a stack, tower, or similar structure. Housed in thiscanopy are electrical contacts, a pair of which are fixed, as indicatedat 29, for cooperation with mating contacts carried by the fixture stemI50, all as fully disclosed in Fig. 2 of my above-mentioned patent. Itwill be understood that electrical conductors 2| and 22 pass through thehollow arm 18 for connection with the, fixed contacts 2d, and otherelectrical conductors lead from the mating contacts downwardly throughthe. stem Ida and fixture to energize the lamps within the globes It,all as shown in the above patent, and the details of which form no partof the present invention.

A guiding track 23 is fixed in a generally vertical position on thesupporting structure I9. Obviously, if this supporting structure is awall having a batter or a stack tapering toward the top, the track 23will not be absolutely vertical, but nevertheless, it will extend in agenerally vertical direction. The construction of this track is clearlyshown in Figs. 4, 5, 7 and 8. It is essentially a continuous box beamfrom top to bottom having the general form of the letter 1. One flangemember against the wall of the supporting structure comprises a platenand legs 25 of the outer beam structure secured to the supportingstructure [9 by bolts or other securing means 26. The legs 25 areportions of a continuous sheet of metal which is bent outwardly at rightangles to the plate 26 providing the web portions 21. The outer portionof this sheet forms a rectangular head which includes the laterallyprojecting hollow flanges 28 and the outermost track face 29 which isgenerally parallel to the plate 24'. This track is formed out ofrelatively light metal sheets, say of fourteen or sixteen gauge, which,when bent to the form shownand bolted in position, provides a verystrong track, structurally speaking,

but one requiring a relatively small amount of metal. ihis track isprovided in suitable lengths which are so constructed with slip jointsat their meeting ends, as indicated at 30 in Figs. 1 and 3, that anylength desired may be assembled and the surfaces 2?, 2B and 29 will besubstantially in line and smooth throughout the length of the track. Thedetails of this construction will be more clearly apparent in Figs. 3and 7 where the portions 23 of the lower track section have been cutaway from the web portions 21 sufiiciently to permit the end portions 28and 27- to be bent inwardly, substantially the thickness of the metalrom which the track is formed. These contiguous end portions then slideinto each other, as indicated in Figs. 3 and '7, to provide a continuoustrack with slip joints allowing a certain amount of expansion andcontraction as the temperature changes.

Partition means 3! is preferably provided inside the track for thepurpose of positively separating the electrical conductors from the lampoperating cable as will later appear. This comprises a strip of metalbent U form in section, as viewed in -i, 5 and 7, with the cross piece310 of the U flat against the inside of the portion 29 of the track, andthe legs 3th engaging the inner faces of the web portions 2?.Preferably, deformations 32 of half conical form are struck out from thelegs filb at spaced points therealong in position to engage the walls ofthe hollow flanges 28, as clearly shown in Figs, 4 and 5. The member 3|is thus held against outward movement by its portion Sla and is heldagainst inward movement by the projections 32.

A carriage indicated generally at 33 rides up and down on the track 23and is connected with the lamp by a pair of rods 34 which are analogousto the rods 5! shown in my above-mentioned patent. These rods are heldby set screws or the like in suitable openings in the fixture at theirouter ends, and they enter into sockets 35 formed in bosses 35 on theface of the carriage. As clearly ShOWn in Figs. 5 and 6, short sleeveportions 3? embrace the rods 34, and these are held in place by innerset screws 38 passing into the sleeve 37 and the outer set screws 38which pass through the sleeve and into the rods 3%. As shown in Fig. 6,the sockets 35 may be slightly tapered, as shown at 35, so as to permitthe adjustment of the rods 32, at an angle to hold the lamp horizontalin case the track 23' is not exactly vertical as in the case of slopingstructures mentioned above.

The base structure of the carriage comprises a base plate 58 on which ismounted a wide flat roller 4! adapted to engage the outer face 29 of thetrack over the wide flat surface thereof, so as to give a broad flatbearing against the track. This roller ll is yieldably mounted in thecarriage for movement toward and away from the supporting structure It.To this end, the roller is mount 7 ed on a shaft :12, the opposite endsof which extend through slotted openings 43 in the boss 33 which isintegral with the base plate 43. These slotted openings are at rightangles to the track face 29, and plungers id extend lengthwise of eachslot, bearing gainst shaft 32 at one end, and yieldingly held at theopposite end by a helical spring t5 mounted in a, cup 46, which isthreaded into the boss 35, as clearly shown in Fig. 5. The roller Q! isthus firmly held against the surface 29, but may yieldingly move toaccommodate itself to inequalities in the surface, coatings of ice,corrosion, or the like.

Other rollers are provided to yieldingly hold the carriage againstlateral movement with respect to the track, and preferably, thesecomprise an upper pair 41 and a lower pair 48. Since these rollers arethe same, one pair only will be described. Each roller 27' has a mainroller portion 41a which bears against the outer flange edge 23 of thetrack, that is to say, the surface parallel to the web 21. Each rollerhas a flange portionflb which engages against the track surface 28awhich is that portion of the track flange spaced inwardly from andparallel to the surface 29. Thus, the flange head of the track issqueezed between the roller 4! and the flanges 41b of the rollers M andsimilar flanges 48b of the rollers 48. The rollers 41'! are mounted foryielding movement toward and away from the track in a lateral direction.To this end, each roller is rotatably mounted in an arm 49, and thesearms are pivotally mounted on a pin 59 which is mounted on the base -38.The movement of each arm 49 is controlled by a link 5| which is,pivotally mounted on the end 52a of the roller shaft 52. Each of theselinks extends laterally inwardly and is; flanged at Ma to provide anopening for receiving a pin 53 which in turn is freely held in anopening 54 of a projection 55 integral with the base plate 40. Oppositeends of pin 53 are embraced by short helical springs 56 held in place bynuts 51. Thus, the springs 56 yieldingly hold the flanges 5|a of links5| inwardly so as to permit yielding movement of rollers 41 laterallyaway from the track upon compression of springs 56. The partscontrolling rollers 48 have been given similar reference characters. Itresults from this construction that the rollers 41 and 48 mayaccommodate themselves to inequalities of the track flanges 28, or toaccomulations of ice, corrosion, or the like.

Obviously, the carriage 33 may be removed from the track by spreadingthe rollers 41 and 48 sufficiently for the flanges 41b and 48b to clearthe track.

The hollow track not only provides a strong structure with a minimumamount of metal, but it also provides a continuous closed passagewayfrom bottom to top of the supporting structure. The bolted connection offlanges 25 with plate 24 prevents the entrance of water and moisture atthe back of the track, and means are provided at the top and bottom toprevent the entrance of moisture to the hollow portion of the track. Itherefore utilize the hollow passageway of the track for the guidanceand protection of the lamp operating cable and the electrical conductors2| and 22. Reference will be had first to the operating cable. Myabove-mentioned patent shows a latching means for holding the stem |5ain its raised position, and the present invention contemplates the useof such latching mechanism. The operating cable 58 is attached to theupper end of stem l5a, as shown in my above-mentioned patent. It thenpasses upwardly around pulley 59 mounted on shaft 69 in the hollow arm8, thence through the hollow arm to the mounting connection 6| and overpulley 62 which is rotatably mounted therein on shaft 63. As cable 58leaves pulley 62, it is in position to pass downwardly through the midportion of the web of the hollow track, as clearly shown in the variousviews.

The electrical conductors 2| and 22, previously described, pass throughthe hollow arm l8 and the fixture 6| to a point directly over the hollowportions of flanges 23 of the track, as clearly shown in Figs. 4, 5 and7. These conductors are housed in the opposite ends of the track flangeand are separated from each other and from the operating cable 58 bymeans of the U-shaped member 3 I, previously described. To comply withthe code relating to such matters in some places, means is provided atspaced points along the track for supporting and insulating theconductors 2| and 22. One such supporting and insulating device is shownin Figs. 3 and 8. These are preferably provided in short track sectionswhich are fitted between longer track sections by utilizing structuressimilar to that shown in Fig. 7. Such special sections will have aspecial U- shaped member 64 fitting between the track web portions 21and supporting a bracket 65 having a down turned flange or lip 65a whichextends through a suitable slotted opening in the member 64 and may bewelded thereto, if desired. Riveted on the bracket 65 is a sheet ofinsulating material 65 having openings 61 at its opposite ends forreceiving and holding the conductors 2| and 22. The conductors fittightly in the opening 61 so that the weight of the conductors issupported as required by code regulations in some places. At the sametime, the insulator member 66 maintains the conductors in a separatedposition.

Preferably, I form the hollow arm I8 and the fixture 6| according to theteachings of United States Patent No. 2,403,355, granted July 2, 1946,to Thayer B. Farrington, Wade T. Keller and Robert K. Farrington, towhich reference may be had for greater detailed description, if desired.The arm I8 is shorter than the arm 6 shown in the last mentioned patent,but it is provided with a partition |8a in all respects similar to thepartition ||Ba of the last mentioned patent. Likewise, the shrouding 68around pulley 59 and the shrouding 59 around the pulley 62 may bearranged according to the teachings of the last mentioned patent, so asto provide a continuous separation throughout the arm |8 and the fixture6| between the operating cable 58 and the electrical conductors 2| and22. The bottom plate 65a is arranged with suitable openings, onecorresponding to the hollow space between the walls 21 of the track webportion, and one corresponding to the hollow flange portion housed bythe walls 28 and 29 of the track. These connections are so arranged thatwater and moisture cannot enter the top of the track, but instead, areprotected by the fixture 6|. In this fashion, the electrical conductors2| and 22 are provided with their own passageway continuously from thehood I! through arm l8, fixture 6| and track 23, clear to the base ofthe supporting structure l9. In like manner, the operating cable 58 isprovided with its own separate passageway through the same parts to thebase of the supporting structure.

At the base of the supporting structure, I have shown a small enclosure19 which may house the electrical connections for conductors 2| and 22and which need not be shown. It also houses support means forthe lowerend of the operating cable 58. Any suitable connection at this point forholding the cable 53 and for providing means for attaching additionalcable thereto when necessary to lower the lamp, would be satisfactory.In fact, the cable 58 might be wound upon a suitable reel at the bottomof track 23, if desired. I prefer, however, to utilize the constructionshown in the copending application of Wade T. Keller and Thayer B.Farrington, Serial No. 514,058, filed December 13, 1943, wherein a link33 attached to the bottom of the operating cable is normally held by ahook 34, as shown in said application, and connector means is providedfor attaching an extra length of cable, when necessary, for lowering thelamp.

It is believed that the operation of the above described device will nowbe apparent. The lamps are normally held in raised position by means ofthe latch, not shown, and with the lamp energized by proper connectionwith the contacts 2B. When it is desired to lower the lamp for anypurpose, cable 58 (or extra cable attached thereto, if desired) is givena slight pull to disconnect the type of latch referred to in my priorpatent, after which the stem |5a is disconnected and the fixture l5carrying the lamps may be lowered, guided by the rods 34 connected withthe carriage 33 which is guided by the track 23. The lamps may thus belowered to any point desired and returned to the upper latched andenergized position when repairs or maintenance operations are completed.The carriage will ride smoothly on the track 23 being clamped thereto intwo difierent planes, as described in connection with the rollers 41, 47and 48. The carriage may be removed from the track, if desired, byspreading the rollers 41 and t8.

Throughout this description and the following description and in theattached claims, I have used the word cable to refer to the member 58.Those familiar with this art will appreciate that flexible chain, rope,or other flexible tension members may be used for this purpose. Itherefore use the word cable throughout the specification and claims asa short term for any such flexible tension member.

In Figs. 9 to 14 inclusive, I have shown a modification of the devicealready described, and only sufiicient explanation will be given for acomplete understanding of the differences between the first and secondforms.

Inthis second form, the track i is of hollow box beam construction fromtop to bottom of the supporting structure 16, but is of diamond headconstruction, as clearly shown in Figs. 11 to 14 inclusive. The diamondhead of the track 11 is connected by web portions 18 with flanges l9,turned outwardly to receive the bolts 88 which secure the flanges 79 toa plate I06 and to the supporting structure it. This, again, gives awater-tight'construction as in the first form. The vertically movablecarriage in this case comprises a base plate 8| having upstanding bosses82 in which are mounted rods 83' which are analogous to the rods 34 ofthe first mentioned form and carrying the fixture IE3 at their outerends. Here again, roller means is provided for yielding motion towardand away from the supporting structure It. This roller 84 is clearlyshown in Figs. 9 and 11 as having a V-shaped periphery complementary tothe ridge 71a of the diamond head track. This roller is rotatablysupported by a shaft 35, the opposite ends of which extend throughbosses 86. integral with the plate 8!. These bosses have slottedopenings 81 extending at. right angles to the track, and plungers 8Sbear against the ends of shaft 85 pressed by springs 89 which are heldin cups 99 threaded into the bosses 85. Thus, the roller 84 isyieldingly held by movement toward and. away from .the track.

Roller means is also provided permitting yielding movement. of'thecarriage laterally of the track. I have shown an upper pair of suchrollers 9| and a lower pair of rollers 92. They are all supported in asimilar manner and therefore, one onlyneed be described; For instance,each roller 9! has a shaft 93 carried by an arm 94 which is. pivota lymounted on the base plate at 95. A link 96 pivotally connected to arm94' at the axis of shaft 93 extends inwardly toward a bracket 9.! on thebase plate 8 I. The bracket has a flange 96a by which it is mounted on apin 98 held in the bracket 91. A spring 99 held by nut Hi0 threaded onpin 98 holds the spring 99 in compression so that roller 9i may movelaterally, as shown by the dot-dash position of Fig. 10, and the pair ofrollers 9| are yieldingly held toward the track by the springs 99.Similar springs 99 urge the pair of rollers 92 yieldingly toward thetrack. As clearly shown in Figs. 9, 11 and 12, the rollers 9| and 92have V-shaped peripheries which are complementary to the ridges 11b ofthe diamond head track. The flanges. Ma and 92a nearer th supportingstructure here perform the same function as that performed by theflanges 41b and 48b of the firstdescribed modification. In other words,the carriage is held on the track by the action of roller 84 and theflanges Sid and 92a. 7

The track of this second modification is of continuousform, as in thecase of the first modification, the trackb'eing'made in sections whichhave slip joint connections with each other, as illustrated in Figs. 9and 13; Here, the web portions 118' have been cut away from the diamondheadportions TI and bent inwardly by the thickness of the metal so thatthe upper end of one track. section is a sliding fit in the lower end.of' the section above it, and the surfaces of the track alongtwhich therollers move are smooth and practically uninterrupted.

Here, as in the first described modification, means is provided atspaced'portions along the track, as shown in Fig. 14 for supporting andinsulating the conductors 2| and 22 from each other. These are analogousto the conductors 2! and 22 previously described, and are connected tothe energizing contacts 20 in. exactly the same manner. The constructionin Fig. 14 comprises a bracket member l0! welded or otherwise: securedto the diamond head trackv portion 11-. A bracket [02 extends through aslotted opening in bracket [BI and is provided with. a down-turned lipH33 by which it is held. in place. Riveted or otherwise secured to thebracket I02 is a sheet of insulating material H14 provided with endopenings I95 which grip the conductors 21' and 22. The cable 53' extendsthrough the hollow portion of the track between the web portions 78,,and the brackets HII maintain a practical separation between the cable58 and the conductors 2| and 22' throughout the length of the track.

The upper and lower ends of the track of. Figs. Ste 14. may be closed bythe housings 6i and H3 respectively, as in the case of the firstdescribed modification, so that no moisture getsinside. the

track.

Itwill be noted that in the form of my device shown in Figs. 9 to 14inclusive, the plate I06 secured to the supporting structure it has beengiven a special form. 'A central rib [96a is formed running verticallyof the track and of just sufiicient width to fit between the webs 18 ofthe outer track member when the same. is properly assembled. Preferably,also, edge flanges I061) are turned upwardly at an angle to the plate[05, these flanges being so spaced: from the rib l-llfia that the flange19 of the outer track member will nest between the rib 106a and one ofthe flanges 36b, as clearly shown in Fig. 12. This construction servesto strengthen the plate I and stifien thesame, while at the same time,providing accurate spacing for the webs l8 and flanges 19 of the outertrack member;

Obviously, this: improvement could be applied to plate of the firstdescribed form, if desired.

In operation, the second modification, like: the first, provides freemovement of the carriage up and down on the track controlled by cable58" and the carriage may be removed from. the track by, spreading thepairs of rollers 91 and 92. This form of carriage will y-ieldingly ride'over any ice or corrosion, or uneven surfaces on the track withoutdanger of the carriage leaving the track unintentionally.

What I claim is:

1. In combination, a supporting structure; an arm in elevated fixedrelation to said structure, a lamp and carriage assembly dependent fromsaid arm, a. cable passing over said arm and attached to said; assembly'for raising. and lowering the same, electrical means for energizing saidlamp when elevated, a hollow track extending downwardly from said arm,said track having a web portion secured to said structure and anenlarged head portion outwardlyfrom said web portion, said head portionhaving a flat outer face and two nd faces at right angles to said outerface and inner face portions adjacent said end faces and substantiallypara lel to said outer face, roller means on said carriage engaging saidouter face and yieldably movable toward and away from the same, a pairof rollers engaging said two end faces respectively and yieldinglymounted on said carriage for movement toward and away from the same,said last named rollers having flanges engaging said inner faceportions, and said cable extending through the hollow of said track.

2. In combination, a supporting structure, an arm in elevated fixedrelation to said structure, a lamp and carriage assembly dependent fromsaid arm, a cable passing over said arm and attached to said assemblyfor raising and lowering the same, electrical means for energizing saidlamp when elevated, a hollow track extending downwardly from said arm,said track having a web portion secured to said structure and anenlarged head portion outwardly from said web portion, said head portionbeing of generally diamond shape with a diagonal thereof parallel tosaid web portion, said head portion providing an outer ridge and twolateral ridges extending along said track, roller means on said carriageand having a V-shape groove engaging said outer ridge, said roller meanshaving a yieldable mounting on said carriage for movement toward andaway from said track, other rollers on said carriage and having V-shapegrooves engaging said lateral ridges, said last named rollers havingyieldable mountings on said carriage for movement toward and away fromsaid track, and said cable extending through the hollow of said track.

3. In combination with a vertical support, a generally vertical trackhaving a web portion secured to said support and having an enlarged headportion spaced from said support, a carriage adapted to traverse saidtrack, roller means rotatably mounted on said carriage on axes parallelto said web portion and adapted to engage opposite sides of said headportion, said roller means having mounting parts arranged for movementof said roller means toward and away from said head portion and theplane of said web portion in a vertical plane at right angles to saidweb portion, said roller means yieldingly engaging said track, saidroller means including roller parts engaged on the support side of saidhead portion, whereby to hold said carriage on said track, said movementof said roller means away from said head portion being sufficient topermit said last named roller parts laterally to clear said headportion.

4. A hollow track for the purpose described comprising a base structure,a sheet of metal bent to provide spaced web portions extending away fromsaid base, each of said web portions having a flange bent outwardlytherefrom adjacent said base and secured thereto, a head portion joiningsaid web portions at the side of said track away from said base, saidhead portion being of generally diamond shape in section and having oneof its diagonals parallel to said web portions, elongated flexiblemembers extending one through said diamond head portion and one be- 10tween said web portions, and partition means inside said tracl:separating said flexible members.

5. In combination with a vertical support, a generally vertical trackhaving a web portion secured to said support and having an enlarged headportion spaced from said support, a carriage adapted to traverse saidtrack, rotatable roller means on axes parallel to said web portion andon opposite lateral sides of said track, pivoted means on said carriageattached to said roller means and arranged for movement of said rollermeans generally in a vertical plane at right angles to said web portiontoward and away from said head portion and from the plane of said webportion, yieldable means forcing said roller means into engagement withsaid track, said roller means including roller parts engaged on thesupport side of said head portion and holding said carriage on saidtrack, said movement of said roller means away from said head portionbeing suiiicient to clear said roller parts from said head portionwhereby said carriage may be removed from said track intermediate theends of the latter.

6. In an organization comprising a supporting structure and electricalcontacts in an elevated position on said structure and an electricallamp mounted on a carriage and providing an assembly for movementbetween a lowered position for servicing and a raised position with saidlamp in electrical communication with said contacts; the combination ofa generally vertical hollow track having a web portion secured to saidsupport and having an enlarged head portion spaced from said support, acarriage adapted to traverse said track, roller means rotatably mountedon said carriage on axes parallel to said web portion and adapted toengage opposite sides of said head portion, said roller means havingmounting parts arranged for movement of said roller means toward andaway from said head portion and the plane of said web portion in avertical plane at right angles to said web portion, said roller meansyieldingly engaging said track, said roller means including roller partsengaged on the support side of said head portion, whereby to hold saidcarriage on said track, said movement of said roller means away fromsaid head portion being sufficient to permit said last named rollerparts laterally to clear said head portion, a cable connected with saidlamp and carriage assembly for raising and lowering said lamp, a pulleyhaving a fixed mounting near the top of said track, said cable passingover said pulley and down through the hollow of said track, electricalconductors connected with said contacts for supplying energy thereto,said conductors extending from said contacts downwardly through thehollow of said track, and partition means inside of the hollow of saidtrack separating said cable from said electrical conductors.

THAYER B. FARRINGTON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 304,795 Butz Sept. 9, 1884426,558 Dithridge Apr. 29, 1890 547,246 Drake Oct. 1, 1895 939,039Lawrence Nov. 2, 1909 2,364,155 Martineau Dec. 5, 1944

